Senior U.S. officials say they are unhappy with the pace of reconstruction in Iraq and the negative media attention that has been getting. By replacing the top tier of the U.S. civil authority in Iraq, as well as several other senior members of the civil administration team, the Bush administration hopes to speed up Iraq's post-war recovery.

The installation of former State Department official Paul Bremer as chief of reconstruction efforts, supplanting retired General Jay Garner, is only the tip of an abrupt wider shakeup affecting many of the senior-most officials in the U.S. civil administration in Iraq.

Among those being replaced is Barbara Bodine, a former U.S. ambassador who was charged with overseeing reconstruction for the Baghdad region. Other changes at the top levels are also expected.

Officials privately concede that things have not gone as well as expected in the aftermath of the war. One month into the occupation of Iraq, crime and looting are rampant. Many essential services, such as power and clean water have only been sporadically restored. The economy is in a shambles.

Patrick Basham, a senior fellow at the Cato Institute in Washington, says the Bush administration had to take action. "It's being done principally because all of the news reports out of Iraq are bordering on the embarrassing for the Bush administration," he said. "The feel of the reconstruction is not good. And the Bush White House has decided that they need to, at the very least, change the faces."

Some analysts blame the post-war chaos on poor planning for reconstruction by U.S. officials. But others say the fault was not in the planning, but the execution of the plans.

Roberta Cohen, a senior fellow in Foreign Policy Studies at the Brookings Institution, says the U.S. government has been terrified of seeming to be a colonial-style-occupier in Iraq. That, she says, caused U.S. officials to tread so carefully in Iraq that their actions came across as timid, rather than forceful.

"In my opinion, the United States has been a very reluctant occupier. It hasn't exerted authority," he said. "And everybody's beginning to see it is chaotic there, people coming forward, Iraqis, to take over cities, to do what an occupying power should do. It's become clear that the team we sent out there has not been as effective as it should have been. And that's why there was a shakeup," she said.

But the shakeup is also widely seen as part of a broader political struggle between the military minds of the U.S. Defense Department and the diplomats of the State Department. The defense establishment, having won the war, took control of reconstruction as well. Mr. Basham of the Cato Institute says the appointment of Mr. Bremer over General Garner is in some ways an attempt to placate both camps.

"I think what it's really about, it's about [Defense Secretary] Donald Rumsfeld and [Deputy Defense Secretary] Paul Wolfowitz at the Defense Department ensuring that the people they're most comfortable with, trust the most to do the best job here are in place. They thought they had that with Garner, but it didn't work out," he said. "And so, the attempt is to put in someone like Ambassador Bremer, who is trustworthy from the Pentagon's point of view, and has the added bonus of being well-regarded at the State Department."

Ms. Cohen says Mr. Bremer and his new team should be more forceful in exerting their authority.

"They are bringing in somebody who has a reputation as a tough guy, as they say. If that means there will be more willingness to exert authority, that is probably a very good thing," he said.

Mr. Bremer arrived in Iraq Monday, and General Garner is expected to leave after a short transition of perhaps a week or two.